Can't see how it could hurt unless. . .

you put it too close or forget about the thing all night (that's what I'd do) and somehow melt your tires, grips. . .. A regular fan might get the same results unless it's really cold and humid in your garage. Perhaps a fan/space heater combo would let you use the heat, but from a distance that's less prone to catastrophe.

Are parts of the bike very hot to the touch after this treatment? If you can leave the bike in this setup for 30 minutes and the parts closest to the heater are just a little warm I think you should be ok.

Disclaimer: The preceeding is meant for novelty purposes only and should not be construed as advice

The heater is not close enough to get it really hot - just mildly warm. I have it on a timer so it kicks off in 30 mins. I am mostly curious if it will promote corrosion in any way...

Might want to up your service intervals on stuff with all the water. Heating it and getting the water off and out of the bike should minimize corrosion. Might want to let things warm up and bounce the bike around a little to get the water out of areas it's trapped in before you set it overnight.

Yes this can cause corrosion on steel parts. Rust is formed by...

The heater is not close enough to get it really hot - just mildly warm. I have it on a timer so it kicks off in 30 mins. I am mostly curious if it will promote corrosion in any way...

...water evaporating off steel, not contacting it. Your chain is likely most vulnerable, but if you use a good lube, and keep it lubed, it may not become a problem. There's a bit of a catch 22 here, if you think the chain needs lubing after a wet winter ride, you don't want it to rust, but you don't want to clean and lube it before wiping off the dried dirt from the rest of the bike. You can wrap it in a rag if you do, or take it off the bike to clean/lube. The best way to avoid rust forming while waiting for the bike to dry, is to make sure the chain is lubed well BEFORE the ride, and hopfully not washed off by the wetness of the ride. Other parts that are vulnerable are steel bolts, skewer rods, and axles, and may need to be given a light coat of grease (esp downtube bottle bolts), depending on the conditions you live in.

I live in a wet climate, and have experienced spotty rusting on all mentioned parts even without resorting to a space heater, and I don't ever turn on the heat in the room the bike is stored in either. This is not to say using your method is unwise, it just speeds up evaporation and should be done so with proper lubing.

Yeah - I kinda thought the evaporation bit was the problem...

Do you think that the heater is then a bad idea?
My bikes are all aluminum and Ti, so I don't need to worry about the frame so much and I prelube my chain with wet pedros, but there are some steel bolts and stuff on the bike.

Part of the reason I do it is because I get slush in hard to reach places on my frame (truth). The other part is that I am always in a hurry after a ride.

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Don't get me wrong, I love time savers, esp when it comes to bike...

Originally Posted by sodade

Do you think that the heater is then a bad idea?
My bikes are all aluminum and Ti, so I don't need to worry about the frame so much and I prelube my chain with wet pedros, but there are some steel bolts and stuff on the bike.

Part of the reason I do it is because I get slush in hard to reach places on my frame (truth). The other part is that I am always in a hurry after a ride.

...maintenence, I was just pointing out some trouble spots. If you keep an eye on them, lube or treat them somehow, you should be OK. Of course if you're a Ti and aluminum guy, you could start doing the Ti bolt upgrade thing, just make sure you use antiseize where they screw into aluminum parts, otherwise, grease is OK. On the one hand this sounds mostly like a winter only thing for you, on the other hand, Ti bolts are lower maintenence, lighter weight, and increase the resale value of your steed.
As for the space heater (sounds like you've done some remodeling too), just try not to blow dry your dog with it, poor thing might wind up with the frizzies, dry skin, or worse, extra crispy!